Quinolone alkaloids with inhibitory activity against nuclear factor of activated T cells from the fruits of Evodia rutaecarpa

Nine quinolone alkaloids (1 - 9) from the fruits of Evodia rutaecarpa were investigated for their inhibitory activity on nuclear factor of activated T cells (NFAT)-dependent transcription in comparison with nuclear factor (NF)-κB-dependent transcription using a reporter gene assay. These alkaloids showed inhibitory effects against NFAT activity, with IC₅₀ values between 0.91 μM and 15.91 μM. Of the N-methylated quinolones, the longer aliphatic side chain at the quinolone ring showed stronger inhibition of NFAT activity. These N-methylated compounds showed comparable inhibitory effects against NF-κB activity. However, quinolone alkaloids without the N-methyl group showed a more selective inhibition of NFAT activity.